It is becoming more common to replace a missing tooth with a prosthetic tooth that is placed upon and attached to a dental implant. The dental implant serves as the artificial root in that it integrates with the jawbone. The prosthetic tooth preferably has a size and a color that mimics the missing natural tooth. Consequently, the patient has an aesthetically pleasing and structurally sound artificial tooth.
Current methods by which the prosthetic tooth and implant are completely integrated into the patient's mouth require six to ten months, and sometimes longer, because two distinct, time-consuming steps are involved. First, the implant is inserted into the jawbone and covered by suturing the overlying gingival tissue. Covering the implant with the overlying gingiva is needed to minimize the likelihood of infection around the implant. Covering the implant also helps to guard against any disturbances of the implant that may slow its rate of osseointegration. The implant then osseointegrates with the jawbone for a period, usually in the range of three to six months.
After osseointegration is complete, the second step is encountered in which the gingiva is again cut open and a healing abutment is placed onto the implant. The overlying gingiva is sutured to allow it to properly heal around the healing abutment. Thus, when the prosthetic tooth is eventually placed upon the implant, the gingiva nicely conforms around the prosthetic tooth. However, it typically takes four to eight weeks before the gingiva is healed and the prosthetic tooth can be placed on the implant to complete the overall process. These implants can be referred to as "subgingival implants."
Single-stage implants or "transgingival implants" simultaneously promote osseointegration and the healing of the gingiva. This is accomplished by providing an implant that has a portion that integrates with the jawbone and a portion that extends through the overlying gingiva so that the gingiva properly heals therearound. Thus, the four to eight week gingival healing process occurs during the three to six month period of osseointegration. Consequently, the patient is fitted with a prosthesis in a shorter period of time. And, the gingiva is lacerated and sutured one less time compared with two-stage systems which reduces the trauma to that region, the discomfort experienced by the patient, and the overall cost because the number of dental procedures is minimized.
It is sometimes desirable to convert a subgingival implant to the configuration of a transgingival style or vice versa. For example, if one style is best suited for installation in a first site in a patient's jawbone, but another style is best suited for installation in another site, the restoring dentist seeking to fashion a bridge supported on implants installed in both sites might prefer to convert one style to the other in order to make the bridge using common components. Similarly, if a restoring dentist has on hand implants of one style and components for a new improved style become available, for reasons of economy it might be desirable to convert the available implants to the new styles so they can be used with the new components. However, known transition components introduce gaps between the components and present alignment problems for the restoration components.
Furthermore, during the preparation of dental restorations supported on artificial roots implanted in living jawbone, it is frequently useful to provide a temporary cover for a post or abutment (that eventually holds the artificial dentition) supported on a transgingival implant. It is also desirable to prevent the gingival tissue from collapsing around the transgingival implant or to maintain an opening in the tissue at least until temporary dentition is made. This invention also relates to a temporary cap useful to cover such abutments and posts for a transgingival implant.